Heat exchangers



Sept. 27, 1966 R. w. KRITZER HEAT EXCHANGERS Filed May 8, 1964 FROM CQNDENSER INVENTOR.

R/C'HARD W. KR/TZER United States Patent 3,275,071 HEAT EXCHANGERS Richard W. Kritzer, Chicago, Ill., assignor to Peerless of America Incorporated, Chicago, Ill., a corporation of Illinois Filed May 8, 1964, Ser. No. 365,893 Claims. (Cl. 165-121) This invention relates to heat exchangers and, more particularly, heat exchangers which are particularly well adapted for use as evaporators in refrigeration systems, or the like.

It is a primary object of the present invention to afford a novel heat exchanger for refrigeration apparatus, and the like.

Another object of the present invention is to enable good heat transfer between a panel-type heat exchanger and the surrounding atmosphere to be accomplished in a novel and expeditious manner.

Yet another object is to afford a novel evaporator of the panel-type, wherein fan units for blowing air laterally across the outer faces of the evaporator are constituted and arranged thereon in a novel and expeditious manner.

A further object is to enable a novel evaporator of the aforementioned type to be afforded which is relatively smooth and free from dirt-accumulating areas.

Another object is to afford a novel evaporator of the aforementioned type which may be readily, thoroughly cleaned by wiping or washing with a cloth, or the like.

Another object of the present invention is to afford a novel heat exchanger of the aforementioned type which is practical and eflicient in operation and which may be readily and economically produced commercially.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show a preferred embodiment of the present invention and the principles thereof and what I now consider to be the best mode in which Ihave contemplated applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

FIG. 1 is a side elevational view of a heat exchanger embodying the principles of the present invention;

FIG. 2 is an enlarged sectional view taken substantially along the line 22 in FIG. 1; and

FIG. 3 is a fragmentary elevational view of a portion of the heat exchanger shown in FIGS. 1 and 2, looking in the direction of the arrows 33 in FIG. 2.

A heat exchanger 1, embodying the principles of the present invention, is shown in the drawings to illustrate the presently preferred embodiment of the present invention.

The heat exchanger 1 is of a type which is particularly well adapted for use as an evaporator in a reach-in refrigerator, and the like. It includes a panel 2 which embodies two plies or sheet members 3 and 4 adhesively secured together in face-to-face relation-ship to each other, with the oppositely disposed outer faces 5 and 6 of the sheet members 3 and 4, respectively, being relatively smooth and free of shap bends, openings, and the like, in which dust, dirt or other foreign material may accumulate, and from which it would be relatively diflicult to remove such foreign material.

The panel 2 is preferably substantially rectangular in shape, having substantially parallel top and bottom edges 7 and 8, respectively, and substantially parallel side edges 9 and 10, respectively, FIG. 1.

The outer peripheral edge portions 11 and 12 of the sheet members 3 and 4, respectively, throughout the periphery of the panel 2, preferably flare outwardly away from each other to afford an outwardly opening recess or channel 13, and the outermost edge portions of the peripheral edge portions 11 and 12 at the bottom of the panel 2 are preferably bent upwardly and outwardly to atford upwardly opening troughs 14 and 15, respectively, FIG. 2, for purposes which will be discussed in greater detail presently.

An elongated passageway affording a coil 16 is formed in the panel 2 between the sheet members 3 and 4 for feeding working fluid, such as, for example a refrigerant through the panel 2, the coil 16 winding through a tortuous path, which includes a plurality of substantially parallel, straight legs 17 interconnected at alternate opposite ends by bends 18. The coil 16 extends from an inlet opening 13 in the upper end of the side edge 10 of the panel 2 downwardly toward to the bottom edge 8 of the panel 2 and then upwardly along the side edge 10, and terminates at its other end in an outlet opening 20 in the side edge 10 below the inlet opening 19, FIG. 1.

The panel 2 has a circular-shaped opening 21 extending through the center thereof transversely to the sheet members 3 and 4, with four substantially L-sha-ped flanges or ears 22, 23, 24, and 25, FIGS. 2 and 3, formed from the sheet members 3 and 4, extending from the peripheral edge of the opening 21 to afford mounting brackets for a purpose which will be discussed in greater detail presently. Each of the ears 22-25 includes a long leg 26 and a short leg 27, FIG. 2, with the long leg 26 projecting sub stantially perpendicularly outwardly from the main portion of the face 6 of the panel 2, and the short leg 27 being disposed substantially perpendicular to the long leg 26 and projecting from the free end portion thereof substantially radially inwardly relative to the opening 21.

The sheet members 3 and 4 of the panel 2 are adhesively secured together throughout substantially the entire area of their inner faces, except at the peripheral edge portions 11 and 12 thereof, and at the portions thereof affording the coil 16, these latter portions of the sheet members 3 and 4 being bowed outwardly away from each other, FIG. 2, to afford the aforementioned passageway or coil 16 for the flow of working fluid through the panel 2. Outwardly of the opening 21, the panel 2 is preferably imperforate, and the outer faces 5 and 6 thereof are relatively smooth, so that it may be readily cleaned by wiping or washing it with a cloth.

A suitable power unit in the form of an electric motor 28 is mounted in the opening 21 in the panel 2, with the outer periphery of the housing 29 of the'motor 28 preferably being disposed in the opening 21 with a relatively snug, but freely slida'ble fit, and with one end 30 of the housing 29 disposed in abutting engagement wit-h the shorter legs 27 of the ears 22-25, the motor 28 being releasably secured in such position by suitable means such as, for example, screws or bolts, not shown, inserted through openings 31 in the ears 22-2 5, FIG. 3, into the end 30 of the motor housing 29.

The motor 28 includes a drive shaft 32 which projects outwardly from both ends of the housing 29, FIG. 2, and two fans 33 and 34 are mounted on respective end portions of the drive shaft 32 and secured thereto for rotation therewith. The motor 28 is preferably of such size, and the fans 33 and 34 are prefer-ably so constituted and arranged thereon, that the fans 36 and 34 are disposed outwardly of, and relatively closely adjacent to the outer faces 5 and 6 of the sheet members 3 and 4, respectively. The blades of the fans 33 and 34 are of such shape and configuration that during operation of the motor 28, when the fans 33 and 34 are being rotated by the drive shaft 32, the fans 33 and 34 are effective to draw air inwardly, and force it against and laterally outwardly across the faces 5 and 6, respectively of the panel 2 in contact therewith. It has been found that in an evaporator embodying the construction of the heat exchanger 1, wherein refrigerant is flowing through the coil 16, the heat transfer between the refrigerant in the panel 2 and the atmosphere surrounding the panel 2 is increased three or four times when air is force in this manner laterally across the outer faces 5 and 6 of the panel 2, as compared to operation of the same heat exchanger without the fans 33 and 34 being rotated.

Preferably, the heat exchanger 1 includes a suitable electrical resistance element, such as, a suitable resistance cable 35 mounted in the channel 13 in the outer periphery of the panel 2, and extending substantially around the periphery of the channel 2. The ends 36 and 3 7 of the resistance cable 35 may be connected to a suitable source of electric power, not shown, for intermittently feeding electric current through the cable 3 5 to thereby afford heat for defrosting the panel 2 in a manner well known in the art. The troughs 14 and 15 at the bottom of the panel 2 afford containers for receiving any liquid which may run downwardly across the outer faces 5 and 6 of the panel 2, such as, for example, the melt afforded by defrosting operations, and the like, and the liquid thus accumulated in the troughs 1-4 and 15 may be permitted to drain therefrom into a suitable container therefor, or through a drain opening, not shown.

The heat exchanger 1 shown in the drawings is of a type which is particularly well adapted for use as an evaporator in a refrigerator having two cooling compartments, the panel 2, in such an installation, affording the partition wall dividing the two compartments. However, it will be appreciated by those skilled in the art that a heat exchanger, wherein the panel 2 is mounted at the side of a single cooling compartment, with only one of the fans 33 and 34 being embodied therein for circulating the air in that compartment, may be afforded without departing from the purview of the present invention.

In the operation of the heat exchanger 1, refrigerant, for cooling the panel 2, may be fed from a suitable source in a refrigeration system, such as from a compressor and condenser, not shown, into the inlet 19 of the coil 16, from which it may flow through the coil 16 and be discharged therefrom through the outlet 20 to be returned to the aforementioned compressor. Preferably, the motor 28 is operating during all cooling cycles of operation of the heat exchanger 1 so that the fans 33 and 34 are effective to force the air in the respective compartments, within which they are mounted, laterally outwardly across the outer faces 5 and 6, respectively, of the panel 2 in intimate contact therewith. With such construction and operation, the air within the compartments exposed to the faces 5 and 6 of the panel 2 is highly effectively cooled.

Preferably, when the heat exchanger 1 includes a defrosting unit, such as the resistance cable 35 embodied in the preferred form of the invention illustrated in the drawings, the motor 28 is stopped, by suitable controls, not shown, during a defrosting cycle of operation, so as not to retard the defrosting operation by the forced flow of the cold air in the compartments across the outer faces 5 and 6 of the panel 2.

From the foregoing it will be seen that the present invention affords a novel heat exchanger which is particularly well adapted for use as an evaporator in a refrigeration system, and the like, and which may be quickly and easily cleaned.

Also, it will be seen that the present invention affords a novel heat exchanger which is practical and efficient in operation, and which may be readily and economically produced commercially.

Thus, while I have illustrated and described the preferred embodiment of my invention, it is to be understood that this is capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. A heat exchanger comprising (a) a two-ply panel,

(b) each of said plies having an inner face and an outer face,

(c) said inner faces being disposed in juxtaposition to each other throughout the major portion of their areas,

( d) said plies defining a passageway therebetween for feeding refrigerant through said panel,

(e) a motor mounted on and carried by said panel in inwardly spaced relation to the outer periphery thereof substantially centrally of said panel, and

(f) fan blade means mounted on, and operatively connected to said motor for rotation thereby in -'a direction effective to feed air inwardly against, and then outwardly substantially across and in contact with the entire outer surface of at least one of said outer faces,

(g) said outer faces being substantially unobstructed outwardly of said motor.

2. A heat exchanger as defined in claim 1, and in which (a) said fan blade means are disposed in position to so feed said air against and across both of said outer faces.

3. A heat exchanger as defined in claim 1, and in which (a) said panel is imperforate transversely to said outer faces substantially throughout the area thereof exteriorly of said motor.

4. A heat exchanger as defined in claim 1, and in which (a) said panel 1) is substantially upright, (2) has a lower edge portion, and

(b) upwardly opening trough means project outwardly from said lower edge portion.

5. A heat exchanger as defined in claim 1, and in which (a) said panel has a recess therein substantially centrally of said panel, and

(b) said motor is mounted in said recess.

References Cited by the Examiner UNITED STATES PATENTS 2,368,392 1/1940 Young M -125 2,662,748 12/1956 Huber 165-125 X 2,670,611 3/ 1954 Fagerberg 62-290 2,777,300 1/1957 Palmer 1651-70 X 2,992,545 7/1961 Walker 165-470 X FOREIGN PATENTS 266,305 =1/1950 Switzerland.

ROBERT A. OIJEARY, Primary Examiner.

FREDERICK L. MAT'IESON, IR., Examiner.

T. W, STR EULE, Assistant Examiner, 

1. A HEAT EXCHANGER COMPRISING (A) A TWO-PLY PANEL, (B) EACH OF SAID PLIES HAVING AN INNER FACE AND AN OUTER FACE, (C) SAID INNER FACES BEING DISPOSED IN JUXTAPOSITION TO EACH OTHER THROUGHOUT THE MAJOR PORTION OF THEIR AREAS, (D) SAID PLIES DEFINING A PASSAGEWAY THEREBETWEEN FOR FEEDING REFRIGERANT, THROUGH SAID PANEL, (E) A MOTOR MOUNTED ON SAID CARRIED BY SAID PANEL IN INWARDLY SPACED RELATION TO THE OUTER PERIPHERY THEREOF SUBSTANTIALLY CENTRALLY OF SAID PANEL, AND (F) FAN BLADE MEANS MOUNTED ON, AND OPERATIVELY CONNECTED TO SAID MOTOR FOR ROTATION THEREBY IN A DIRECTION EFFECTIVE TO FEED AIR INWARDLY AGAINST, AND THEN OUTWARDLY SUBSTANTIALLY ACROSS AND IN CONTACT WITH THE ENTIRE OUTER SURFACE OF AT LEAST ONE OF SAID OUTER FACES, (G) SAID OUTER FACES BEING SUBSTANTIALLY UNOBSTRUCTED OUTWARDLY OF SAID MOTOR. 